Suikoden 2 is maybe the finest example of a traditional japanese console rpg that I've ever played. Great story, character design, and music. The enemy encounter rate is low, and there are many secrets to be found. Only downside is the mediocre graphics. The same applies to Suikoden 1, but as I recall it is much shorter and the graphics even worse.
Lunar is another outstanding rpg, originally from the Sega CD but ported to psx/saturn. Psx version is really good but much harder than the Sega Cd version, and the final boss is so hard it nearly ruined the game. Lunar II was also ported to psx but I only played the Sega CD version, which is awesome. Like Suikoden, these games aren't exactly pushing the graphical limits of the psx but if you can look past that you'll love this series.
FYI, these games have become cult classics and are still worth a lot of money. I haven't looked in a long while but I've seen Suikoden 2 go for over $120 on ebay